Certification Topics of NCP-AII Exam PDF Recently Updated Questions [Q25-Q44]

QUESTION 25
An InfiniBand fabric is experiencing intermittent packet loss between two high-performance compute nodes. You suspect a faulty cable or connector. Besides physically inspecting the cables, what software-based tools or techniques can you employ to diagnose potential link errors contributing to this packet loss?

Use ‘ibdiagnet’ to perform a comprehensive fabric analysis, including link integrity checks and error detection.

Monitor the port counters on the InfiniBand switches connected to the compute nodes. Look for excessive CRC errors, symbol errors, or other link-related error counts.

Run ‘ipeff or ‘ibperf between the two compute nodes and analyze the reported packet loss rate. Correlate this with the error counters on the switches.

All of the above

Disable port mirroring.

QUESTION 26
Consider the following ‘ibroute’ command used on an InfiniBand host: ‘ibroute add dest Oxla dev ib0’. What is the MOST likely purpose of this command?

To add a default route for all traffic destined outside the InfiniBand subnet.

To create a static route for traffic destined to LID Ox1a, using the InfiniBand interface ib0.

To configure the MTU size on the ib0 interface to Ox1a bytes.

To disable routing on the ib0 interface.

To configure a static route for traffic destined to IP address Ox1a, using the InfiniBand interface ib0.

QUESTION 27
You are using NVIDIA Spectrum-X switches in your A1 infrastructure. You observe high latency between two GPU servers during a large distributed training job. After analyzing the switch telemetry, you suspect a suboptimal routing path is contributing to the problem. Which of the following methods offers the MOST granular control for influencing traffic flow within the Spectrum-X fabric to mitigate this?

Adjust the Equal-Cost Multi-Path (ECMP) hashing algorithm globally on all switches.

Configure QOS (Quality of Service) policies to prioritize traffic from the high-latency GPU servers.

Implement Adaptive Routing (AR) or Dynamic Load Balancing (DLB) features available on the Spectrum-X switches to dynamically adjust paths based on network conditions.

Manually configure static routes on the Spectrum-X switches to force traffic between the GPU servers along a specific path.

Disable IPv6 to simplify routing decisions.

QUESTION 28
You’ve installed the NGC CLI and successfully configured your API key However, when running ‘ngc registry model download’ , you receive a ‘Permission denied’ error despite having valid credentials. What are possible causes and solutions?

The user account running the ‘ngc’ command does not have write permissions to the destination directory specified for the download.

Your API key lacks the necessary permissions to download models from the NGC registry. Contact your NVIDIA organization administrator.

The model you are trying to download requires acceptance of a separate end-user license agreement (EULA) that you haven’t yet accepted.

There is an issue with network connectivity or firewall rules preventing access to the NGC registry. Verify network connectivity and firewall rules.

Models can only be downloaded to specific location.

QUESTION 29
You suspect a faulty NVIDIA ConnectX-6 network adapter in a server used for RDMA-based distributed training. Which commands or tools can you use to diagnose potential issues with the adapter’s hardware and connectivity?

Ispci -v to verify the adapter is detected and its resources are allocated correctly.

ibstat to check the adapter’s status, link speed, and active ports.

ethtool to examine the adapter’s Ethernet settings and statistics.

ping to test basic network connectivity.

nvsmimonitord to monitor GPU metrics and detect anomalies.

QUESTION 30
Consider this Python code snippet used for loading data for a deep learning model:

Assuming the images are stored on a remote file system accessed over NFS, and training is slow due to I/O bottlenecks, which change to the ‘DataLoader’ would MOST directly improve performance?

Increase ‘batch_size’ significantly (e.g., to 256).

Decrease ‘num workers’ to 1.

Increase ‘num_workers’ to a value equal to the number of CPU cores on each training node.

Set in the DataLoader.

Implement multithreaded data loading inside _getitem

QUESTION 31
You’re troubleshooting a DGX-I server exhibiting performance degradation during a large-scale distributed training job. ‘nvidia-smu shows all GPUs are detected, but one GPU consistently reports significantly lower utilization than the others. Attempts to reschedule orkloads to that GPU frequently result in CUDA errors. Which of the following is the MOST likely cause and the BEST initial roubleshooting step?

A driver issue affecting only one GPU; reinstall NVIDIA drivers completely.

A software bug in the training script utilizing that specific GPU’s resources inefficiently; debug the training script.

A hardware fault with the GPU, potentially thermal throttling or memory issues; run ‘nvidia-smi -i -q’ to check temperatures, power limits, and error counts.

Insufficient cooling in the server rack; verify adequate airflow and cooling capacity for the rack.

Power supply unit (PSU) overload, causing reduced power delivery to that GPU; monitor PSU load and check PSU specifications.

QUESTION 32
A critical AI model training job consistently fails on a specific GPU server in your cluster after running for approximately 24 hours.
Monitoring data shows a sudden drop in GPU power consumption followed by a system reboot. All other GPUs on the server appear normal. The server has redundant PSUs. What is the MOST likely cause?

A software bug in the A1 model causing a kernel panic specifically triggered after 24 hours of execution.

Thermal runaway on the GPU due to a failing thermal interface material (TIM) between the GPU die and the heatsink.

A transient power supply issue affecting only one of the redundant PSUs, triggering a system-wide protection mechanism.

ECC memory errors accumulating over time, eventually leading to a non-recoverable system fault.

A driver crash, causing the GPU to reset and the system to reboot.

QUESTION 33
You are tasked with installing the NGC CLI on a host that does not have direct internet access. You have downloaded the NGC CLI package to a local repository. Which of the following steps are required to successfully install and configure the NGC CLI in this offline environment?

Transfer the NGC CLI package to the host and install it using ‘pip install .whl’.

Configure the NGC CLI to point to your local package repository by setting the environment variable.

Manually download and install all dependencies of the NGC CLI package using ‘pip install –no-index –find-links=/path/to/dependencies .whl’.

Run ‘ngc config set’ to configure the API key, pointing to a local configuration file.

Only copying the whl file is sufficient, NGC CLI dependencies are always local

QUESTION 34
Consider the following scenario: You have a BlueField-2 DPU installed in a server. You are trying to establish RDMA (Remote Direct Memory Access) communication between the DPU and another server. However, the RDMA connection fails. Which of the following is the most crucial factor to verify in this scenario?

That the clocks on both servers are synchronized using NTP (Network Time Protocol).

That the appropriate RDMA kernel modules (e.g., , ‘ib_uverbs) are loaded on both the DPUand the remote server.

That the TCP window size is properly tuned for high-bandwidth communication.

That the correct MTU (Maximum Transmission Unit) is configured on the network interfaces involved in the RDMA connection.

That the power supply to the DPU is providing sufficient wattage.

QUESTION 35
You are setting up network fabric ports for hosts in an NVIDIA-Certified Professional A1 Infrastructure (NCP-AII) environment. You need to configure Jumbo Frames to improve network throughput. What is the typical MTU (Maximum Transmission Unit) size you would set on the network interfaces and switches, and why?

1500 bytes, as it’s the default and compatible with most networks.

9000 bytes, also known as Jumbo Frames, reduces overhead and improves throughput for large data transfers.

65535 bytes, the theoretical maximum MTU size, for maximum performance.

576 bytes, the minimum MTU size required by IPv4.

Any MTU size between 1500 and 9000 bytes; the specific value doesn’t matter.

QUESTION 36
You are tasked with installing the latest NVIDIA driver on a server running Ubuntu 22.04 for A1 workloads. You have downloaded the driver package ‘NVIDIA-Linux-x86 64-535.104.05.run’. Before installation, what is the most critical step to ensure a smooth process, assuming secure boot is enabled?

Simply run the ‘ .run’ file using ‘sudo ./NVlDlA-Linux-x86_64-535.104.05.run’ .

Disable Secure Boot in the BIOS before installing the driver.

Create a DKMS module and sign the driver with a machine owner key (MOK) for Secure Boot compatibility.

Install the driver using ‘apt install nvidia-driver-535’ and let the system handle Secure Boot automatically.

Ensure the ‘nouveau- driver is blacklisted by adding ‘blacklist nouveau- to ‘letc/modprobe.d/blacklist-nouveau.conf.

QUESTION 37
You’re setting up a cluster with 8 NVIDIA A100 GPUs. Each GPU needs to read 4GB/s from storage to keep it fully utilized. The network connecting the storage and compute nodes has a bandwidth of 25GB/s. What is the maximum number of GPUs that can be simultaneously saturated with data without exceeding the network bandwidth?

2

4

6

8

5

QUESTION 38
You are configuring a network bridge on a Linux host that will connect multiple physical network interfaces to a virtual machine. You need to ensure that the virtual machine receives an IP address via DHCP. Which of the following is the correct command sequence to create the bridge interface ‘br0’, add physical interfaces ‘eth0’ and ‘eth1’ to it, and bring up the bridge interface? Assume the required packages are installed. Consider using ‘ip’ command.

QUESTION 39
You need to uninstall all NVIDIA drivers and associated packages from a Linux system cleanly. Which command sequence is the most reliable for achieving this after stopping the display manager (e.g., ‘sudo systemctl stop gdm3’)?

‘sudo apt purge nvidia- (on Debian/Ubuntu-based systems)

Running the .run’ installer with the ‘-uninstall’ option (if the driver was installed this way)

‘sudo yum remove nvidia- (on RHEL/CentOS-based systems)

Deleting the Vusr/lib/nvidia and ‘lusr/share/nvidia directories.

‘sudo dnf remove nvidia- (on Fedora-based systems)

QUESTION 40
A security policy requires you to log all NGC CLI commands executed on a specific host. How can you achieve this without modifying the NGC CLI source code?

Use the ‘history’ command in Linux to view the command history for the user account used to execute the NGC CLI commands.

Implement system-level auditing using tools like ‘auditd’ (Linux) or Windows Event Logging to capture all executed commands, including NGC CLI commands.

Create a wrapper script around the ‘ngc’ command that logs the command and its arguments before executing the actual NGC CLI command.

NGC CLI automatically logs all commands to a file in the ‘/var/log/ngc’ directory.

Configure the NGC CLI to send all commands to a remote syslog server.

QUESTION 41
Which of the following commands correctly configures the NGC CLI to use a specific API key stored in an environment variable named ‘NGC API KEY’?

QUESTION 42
You’re configuring a RoCEv2 network for your AI infrastructure. Which UDP port number range is commonly used for RoCEv2 traffic, and why is it important to be aware of this?

0-1023, because these are well-known ports.

4791 , which is reserved for VXLAN.

49152-65535, the dynamic/private port range, to avoid conflicts with other services.

1024-49151 , the registered port range, for general application use.

Any UDP port number can be used without issue.

QUESTION 43
You are installing four NVIDIAAIOO GPUs in a server, and after installation, you observe that the PCle link speed for one of the GPUs is running at x8 instead of the expected x16. What could be the POSSIBLE causes for this reduced PCle link speed?

The GPU is faulty.

The CPU does not have enough PCle lanes to support all GPUs at x16.

The PCle slot is only wired for x8 speed.

The BIOS/UEFI is configured to limit the PCle link speed for that slot.

All of the above

QUESTION 44
You’re profiling the performance of a PyTorch model running on an AMD server with multiple NVIDIA GPUs. You notice significant overhead in the data loading pipeline. Which of the following strategies can help optimize data loading and improve GPU utilization?
Select all that apply.

Using the ‘torch.utils.data.DataLoader’ with multiple worker processes.

Loading the entire dataset into RAM before training.

Implementing asynchronous data prefetching using ‘torch .Generator’.

IJsing a faster storage system (e.g., NVMe SSD instead of HDD).

Reducing the batch size to decrease the amount of data loaded per iteration.